Loading...
HomeMy WebLinkAboutPA2022-042_20220707_Slope Stability Report Vol I RESPONSE TO CITY REQUEST SLOPE STABILITY ANALYSIS Proposed Residential Construction Tract 4224, Lot 78 1424 Galaxy Drive Newport Beach, California VOLUME I (Text, Appendices A, B, C, and Illustrations) Prepared for: Mr. Eddie Chen 1424 Galaxy Drive Newport Beach, California Project by: R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, California 92660 Phone: 949-2539 | Email: Info@Rmccarthyconsulting.com Project No: 8444-10 Report No: R5-8444 July 7, 2022 R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 July 7, 2022 Mr. Eddie Chen File No: 8444-10 1424 Galaxy Drive Report No: R5-8444 Newport Beach, California 92660 Subject: Response to City Request Slope Stability Analysis Tract 4224, Lot 78 1424 Galaxy Drive Newport Beach, California APN: 117-671-14 References: See attached Dear Mr. Chen: Our slope stability analyses has been completed and the results are provided herein. Our principal conclusion is that, from a geotechnical standpoint, a new home may be safely constructed on the property as proposed. The stability of the property is dependent on maintaining the integrity of the existing caisson and tie-back wall system during demolition, subsequent site excavations, grading and construction activities, and as part of future maintenance and development of the property. Additional recommendations for site construction have been provided as part of our geotechnical report (Reference 36). Such recommendations are considered conservative and prudent for the planned construction. Purpose This report presents the results of a slope stability analysis undertaken at your request to relate the geologic and soil conditions of the natural bluff slope above the Newport Back Bay to the proposed design of a new custom home. We understand that this analysis was also requested as part of the current permit application(s) for the governing agencies including the City of Newport Beach and the California Coastal Commission. Qualifications The slope stability analysis included herein was conducted by Robert J McCarthy, a registered geotechnical engineer in the state of California (No. 2490, Expires 3/31/2024). Mr. McCarthy has over 30 years of experience in geotechnical engineering practice and is qualified to perform the slope stability analysis included herein. He has managed projects in the field of geotechnical engineering and is highly qualified in the engineering design and development of all types of construction including large mass grading developments, commercial, industrial, residential tract July 7, 2022 File No: 8444-10 Report No: R5-8444 Page: 2 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 | email info@rmccarthyconsulting.com and custom homes, public works and infrastructure projects. Mr. McCarthy has directed numerous studies and investigations relating to design of high-rise office buildings, parking structures, podium structures, tilt-up warehouse/office facilities, high end apartments and residential homes. He has overseen complex repairs (including tie-back walls, compaction grout injection, underpinning, segmental retaining walls and geogrid reinforced slopes), defense installations (including airfields and support facilities), highways and highway bridges, major infrastructure pipeline alignments, and regional water treatment plants. He has extensive experience in the design and construction of major earth retaining structures, including work with soldier pile shoring, concrete piers and caissons, geo-jet piers, secant walls, tie-backs and all types of retaining walls. He has also supervised studies for stream channels, groundwater, slope stability, landslides, bluff erosion, and earthquake and vibration effects. Additionally, specific to the subject site, Mr. McCarthy has conducted numerous investigations and repairs of major landslides in southern California where similar earth movement has occurred within sedimentary bedrock materials assigned to the Monterey formation, Modelo formation, and Capistrano formation. Scope of Work The scope of services provided as part of our analysis included the following geotechnical steps, which supplement our referenced geotechnical investigation: 1. Review of collected, pertinent geotechnical and geologic literature, maps and plans. A reference list is included in Appendix A. 2. Review of aerial photographs, both current and historic, to evaluate aspects of the slope history, as listed in Appendix A. 3. Exploratory Boring Logs obtained from investigations on similar sites in the immediate vicinity were reviewed and are included in Appendix B. 4. Laboratory direct shear tests obtained from investigations on this and similar sites in the immediate vicinity were reviewed and are included in Appendix C. 5. Preparation of Geotechnical Cross Sections A-A’, B-B’ and C-C’ in order to relate geologic conditions to the proposed development. The cross sections are shown in plan view on Figures 1 and 4 and the profiles are depicted for A-A’ and B-B’ on Figures 2 and 3. Sections A-A’ and C-C’, are shown as part of the slope stability profiles in Appendix E. The bluff topography was obtained from the County of Orange website and is depicted in Figure 4. 6. Analysis of the field exploration and test data as related to the engineering characteristics of the site and slope stability. 7. The results of Surficial Stability Analysis are included in Appendix D. 8. The results of the Stability Analysis for the bluff slope and caisson and tie-back retention system are included in Appendix E. 9. Preparation of this report and its illustrations. Site Location and Description The site is located at 1424 Galaxy Drive in Newport Beach, California as shown on the attached Location Map, Figure 5. The site description and history are provided in the referenced reports. July 7, 2022 File No: 8444-10 Report No: R5-8444 Page: 3 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 | email info@rmccarthyconsulting.com Slope Stability The northeastern side of the site is located in a designated slope stability area as shown on the City of Newport Beach General Plan and the State of California seismic hazard maps (see References 36 and 39). Therefore, in response to agency request, an analysis of the gross and surficial stability of the slope has been performed. The lot topography generally consists of a level graded building pad. The back of the building pad descends approximately 3.5 feet, over distances of about 10 to 15 feet, to the top of an existing retaining wall at the northeast property line. The exposed height of the retaining wall varies from approximately 5 to 10 feet along the rear (northeast side) of the lot. The retaining wall is supported by a system of caissons and tiebacks that also provide stability to the overall slope. Immediately beyond the northeast property line and wall is an approximate 90- to 100- foot-high bluff slope which descends to the Newport Back Bay. The overall bluff slope gradient varies from approximately 1:1 to 1.5:1 (horizontal: vertical). The approximate layout of the caissons, deadman and anchors for the previous slope repair are shown on Figures 1 through 3. The determination of the locations for the anchors is described in the references. The subject site is bordered by the naturally sloping terrain of the bluff. Based on regional geologic maps, previous geotechnical reports and subsurface explorations, the terrace deposits at the site are poorly bedded and generally considered to be massive. The thickness of the terrace deposits is estimated to be 20 to 30 feet. As stated in the references, the sandy terrace deposits are capped with 3 to 5 feet of compacted clayey sand/ sandy clay fill soil that was placed during the original tract grading to limit water infiltration from the surface. The bedrock is buried below the massive terrace deposits and is exposed on the bluff face. The terrace deposits may be erodible when weathered and exposed to significant amounts of water. The stability may therefore be reduced by atypical events that result in adverse concentrated flows of water, such as water line breaks, adverse drainage and/or heavy rainfall. The bedrock is generally dense and more resistant to erosion. Structural geologic bedding is unfavorable with regard to slope stability due to exposed bedding planes with an out of slope apparent dip component. This condition has resulted in past failures along the bluff, generally due to blocks of the outer sections of exposed sloping ground slipping along the bedding and due to fracturing in the rock. A previous failure below 1424-1430 Galaxy Drive was reported in 1978 due to unbuttressed, daylighted bedding planes. The failure was oblique to the slope along a weak clay seam below the terrace deposits. The failure was attributed to excess water in the terrace deposits as a result of the prolonged rainy season in 1977-78. As a result, the retaining system for the slope was constructed in 1978-1979 to restore the lot and provide support against potential future movement along unfavorable bedding behind the row of caissons. Based on previous reports and collected data, the existing caisson and tie-back system consists of 30-inch diameter cast in drilled hole concrete piles with steel cages extending to depths of at least 56 feet and installed 6 feet on-center. The pile caps are connected by a grade beam. Tie backs are in place through the grade beam at every other pile, 12 feet on-center. The tie-backs are approximately 108 to 116 feet in length and extend to a concrete deadman between the house and Galaxy Drive at 1424 and 1430 Galaxy. A retaining wall extends above the grade beam to the lot grades, which are approximately 10 feet higher. The system was designed for a minimum resistance of 1.5 kips per foot for a caisson length of 56 feet for a total resistance of July 7, 2022 File No: 8444-10 Report No: R5-8444 Page: 4 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 | email info@rmccarthyconsulting.com 84 kips per pile. A plan (Reference 16) showing the design, which appears to be corroborated by photos from the time of the repair in 1978, was also reviewed along with the letters prepared by Douglas E. Moran, Inc. (6-23-78 and 10-25-78). Current observations of the exposed portions of the system are in agreement with the plans. For our analysis, it is assumed that the caisson and tie-back system is designed for the loadings as indicated, and therefore includes caissons 56 feet deep with a capacity of 84 kips per pile and a spacing of 6 feet center- to-center. For simplicity, the tie-backs are not included in the slope stability model since we assume their contribution is to provide an overall balancing moment for the caissons. Given that tie-backs are normally tested to twice the design strength and locked off at 1.5 times the design strength, our analysis is considered to be conservative with regard to the resulting calculated safety factors. The caisson and wall system appears to be performing as intended with no indication of obvious damage or deformation (see Reference 35, report by PMA Consulting, Inc, 5-17-22). Shear strength parameters for our slope stability analysis are based on the results of experience with the soil and bedrock on this and similar sites, direct shear tests from this lot and lots in the vicinity, and on engineering judgement. Strength parameters utilized are considered reasonable and within an appropriate range for the materials encountered and are summarized in Appendix E, Table E-5. Cross sections were prepared to depict the soil profile and underlying geology. Cross section A-A’ is located in the southeast side of the lot and is shown on Figure 2 and in the slope stability analyses results, Figures E-1 through E-24. Cross Section B-B’ is shown on Figure 3 and is located in the northwest side of the lot. Cross Sections A-A’ and B-B’ are approximately parallel to the tie- backs and property lines. Cross Section C-C’ is drawn approximately 35 degrees north of parallel to the tie-backs, which is reported to be the direction of movement of the failure that occurred in 1977-1978. Cross Section C-C’, as shown in Figures EC-1 through EC-24, is therefore considered to be the most critical section. Section A-A’ is representative of a smaller portion of the slope and in a 3-dimensional sense is not particularly representative of the overall slope configuration below 1424 Galaxy Drive. Section B-B’ is in the middle between the two other sections. The results of slope stability analysis performed on Sections A-A’ and C-C’ are included in Appendix E. Our slope stability analyses indicate that Factors of Safety for gross stability of the slope exceeds the minimum generally accepted criteria (i.e., 1.5 Static/1.0 Seismic). Surficial slope stability analysis indicates that the existing slope has a safety factor of about 1.32 in the terrace deposits (Appendix D). The rear slope may be subject to weathering, surficial erosion and shallow slumping, the effects of which will be mitigated by the existing caisson and tie-back wall. No slope modifications are planned that would be expected to reduce these safety factors. Slope stability analyses results are included in the attached Appendices D and E. Building Setbacks from Top-of-Slopes A descending bluff slope with a maximum height of about 90 to 100 feet is located along the south side of the site below the caisson and tieback system and property line wall. The slope has a variable gradient with localized areas of steeper and flatter terrain that vary from approximately 1:1 to 1.5:1. The caisson and tie-back system is essentially providing a deepened July 7, 2022 File No: 8444-10 Report No: R5-8444 Page: 5 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 | email info@rmccarthyconsulting.com foundation and setback for structures on the lot. There is no evidence of significant or excessive tilting or deformation of the wall due to slope creep, active earth pressures or earth movement due to landslide. It is our opinion, as an additional conservative measure, that a minimum horizontal setback of 20 feet, as indicated on City Map S-13A, Setback Map for Dover Shores, for house foundations should be maintained behind the top of slope property line. The recommendations of our report, Reference 36, should be implemented as part of the design and construction. Earthquake insurance would generally be recommended for the home on this lot as would be prudent for most lots along the Back Bay bluff. LIMITATIONS This investigation has been conducted in accordance with, and limited to, generally accepted practice in the engineering geologic and soils engineering field, and in accordance with services provided by geotechnical consultants practicing in the same or similar locality under the same or similar circumstances. No further warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. Conclusions and recommendations presented are based on subsurface conditions encountered or identified in past reports and are not meant to imply that we have control over the natural site conditions. The samples taken and used for testing, the observations made and the field testing performed are believed representative of the general project area; however, soil and geologic conditions can vary significantly between tested or observed locations. The recommendations provided herein are subject to outside review and revision by the various governmental agencies, which may include the City of Newport Beach, County of Orange and the State of California. The agencies, at their discretion, may add requirements to planned construction that vary from the information provided herein. Additionally, requirements of the agencies and their interpretations of relevant codes may change over time and with each individual permit application. Site geotechnical conditions may change with time due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate standards may occur as a result of the broadening of knowledge, new legislation, or agency requirements. The recommendations presented herein are, therefore, arbitrarily set as valid for one year from the report date. The recommendations are also specific to the current proposed development. Changes in proposed land use or development may require supplemental investigation or recommendations. Also, independent use of this report without appropriate geotechnical consultation is not approved or recommended. July 7, 2022 File No: 8444-10 Report No: R5-8444 Page: 6 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 Phone 949 629 2539 | email info@rmccarthyconsulting.com Thank you for this opportunity to be of service. If you have any questions, please contact this office. Respectfully submitted, R MCCARTHY CONSULTING, INC. Robert J. McCarthy Principal Engineer, G.E. 2490 Registration Expires 3-31-2024 Date Signed: 07/08/2022 Attachments: Volume I Figure 1 – Geotechnical Plot Plan Figure 2 – Geotechnical Cross Section A-A’ Figure 3 – Geotechnical Cross Section B-B’ Figure EC-3 - Geotechnical Cross Section C-C’ (excerpt from Appendix E) Figure 4 – Bluff Map Figure 5 – Location Map Figure 6 - Aerial Photo Map Figure 7 - Aerial Image in Northwest Direction Figure 8 - Aerial Image in Southeast Direction Figure 9 - Aerial Image in Southwest Direction Appendix A – References Appendix B – Exploratory Boring Logs Appendix C – Results of Direct Shear Testing Volume II Appendix D – Results of Surficial Slope Stability Analysis Figure D-1 Volumes II and III Appendix E – Slope Stability Analysis Tables E-1 through E-5 Figures E-1 through E-24 Figures EC-1 through EC-24 Computations XXXLOT 78 CLTRACT NO. 4224 M.M. 157/1-14 LOT 77 LOT 79 BASIS OF BEARINGS BENCHMARK INFORMATIONBENCHMARK NO: NB6-14-70DESCRIBED BY OCS 2001 - FOUND 3 3\4" OCS ALUMINUM BENCHMARK DISKSTAMPED "NB6-14-70", SET IN THE SOUTHWEST CORNER OF A 5 FT. BY5 FT. CONCRETE PAD WITH MANHOLE. MONUMENT IS LOCATED ALONG THEEASTERLY SIDE OF SANTIAGO DRIVE AT ITS INTERSECTION WITHNOTTINGHAM ROAD, 32.5 FT. SOUTHERLY OF THE CENTERLINE OF NOTTINGHAMROAD AND 22 FT. EASTERLY OF THE CENTERLINE OF SANTIAGO DRIVEMONUMENT IS SET LEVEL WITH THE SIDEWALK.ELEVATION: 70.275 FEET (NAVD88), YEAR LEVELED 1992 VICINITY MAP GRAPHIC SCALE LEGAL DESCRIPTIONREAL PROPERTY IN THE CITY OF NEWPORT BEACH, COUNTY OFORANGE, STATE OF CALIFORNIA, DESCRIBED AS FOLLOWS:LOT 78 OF TRACT NO. 4224, IN THE CITY OF NEWPORT BEACH, COUNTYOF ORANGE, STATE OF CALIFORNIA, AS PER MAP RECORDED IN BOOK157, PAGES 1 TO 14 OF MISCELLANEOUS MAPS, IN THE OFFICE OF THECOUNTY RECORDER OF SAID COUNTY. PAUL D. CRAFT, P.L.S. 8516 DATE NOTE: SECTION 8770.6 OF THE CALIFORNIA BUSINESS AND PROFESSIONS CODESTATES THAT THE USE OF THE WORD CERTIFY OR CERTIFICATION BY ALICENSED LAND SURVEYOR IN THE PRACTICE OF LAND SURVEYING OR THEPREPARATION OF MAPS, PLATS, REPORTS, DESCRIPTIONS OR OTHER SURVEYINGDOCUMENTS ONLY CONSTITUTES AN EXPRESSION OF PROFESSIONAL OPINIONREGARDING THOSE FACTS OR FINDINGS WHICH ARE THE SUBJECT OF THECERTIFICATION AND DOES NOT CONSTITUTE A WARRANTY OR GUARANTEE,EITHER EXPRESSED OR IMPLIED. LICENSE RENEWAL DATE 12/31/20 PAULD OM INICK C RAFTPROFESSIO N A L LAND SU R VEYORCONCRETE SURFACE LEGEND EXISTING ELEVATION( ) ACASPHALT PAVEMENT TEMPORARY BENCHMARKTBM BLOCK WALLLCCENTERLINEGM GAS METERFSFLFINISHED SURFACEFLOWLINE SET ON A WATER METER (WM)HUNTINGTON BEACH, CALIFORNIA 92646PHONE:(714)488-5006 FAX:(714)333-4440 APEXLSINC@GMAIL.COMELEVATION = 105.33 FEET FFGFINISH FLOOR GARAGENG NATURAL GROUNDCLFCHAIN LINK FENCEEVTELECTRICAL VAULTEGEDGE OF GUTTER WATER METERWM WROUGHT IRON FENCEWIF CHAIN LINK FENCE (CLF)WROUGHT IRON FENCE (WIF)THE BASIS OF BEARINGS SHOWN HEREON ARE BASED ON THE CENTERLINEOF GALAXY DRIVE HAVING A BEARING OF N41°10'00"W PER TRACT NO. 4224,M.M. 157/1-14.FFFINISH FLOORBSBOTTOM STEPICV IRRIGATION CONTROL VALVEPEQ POOL EQUIPMENTTOP OF CURBTCTELEPHONE PULL BOXTPBTOP STEPTSTOP OF WALLTWTOP OF DRIVEWAY XTX 6/25/2020 Figure 1: Geotechnical Plot Plan Location of Tie-backs 1424 Galaxy Drive Newport Beach, CA File: 8444-00 July 2022 0 20 feet N Base map: Apex Land Surveying, Inc.EXPLANATION Location of geotechnical cross section line Estimated location of exploratory hand auger boring Af/Qt/Tm HA-6 Approximate deadman,inferred from constructionphotos and plans Approximate tiebacks, inferred from construction plans HA-1 HA-5 HA-3 HA-2HA-4B’ B A’ A C 1430 Galaxy 1418 Galaxy C’A A’ Af Articial ll Qt Terrace deposits Tm Monterey Formation TRACT 4224 LOT 78 TRACT 4224 LOT 79 1424 Galaxy Figure 2: Geotechnical Cross-Section A-A’ 1424 Galaxy Drive Newport Beach, CA File: 8444-10 July 2022 Estimated location of exploratory boring Af Articial ll Qt Terrace deposits Tm Bedrock (Monterey Formation) Contact between geologic units EXPLANATION Notes: 1.All elevations estimated; figure is idealized. 2.Actual profiles may vary; based on topographic and geologic interpretation. Af Tm Tm QtQt Qt PLPL TD 5’ TD 15’Anchor 2.5:1 line Approximate deadman, inferred from construction photos Limits of proposed new structure TD 4.3’ELEVATION, feetN48°E A A’ 70 100 40 ELEVATION, feet70 100 130 130 40 1010 -20-20 0 30 feet IDEALIZED PROFILE CL Galaxy Drive ? ?? ?? ?? ??? HA-6 (projected 44’ SE) HA-5 (projected 28’ NW) HA-1 (projected 20’ SE) HA-3 (projected 47’ SE) TD 12.5’ Existing structure Oblique (apparent) bedding is shown; True dip is north (out of page) Existing structure and limits of remodel expansion Figure 3: Geotechnical Cross-Section B-B’ 1424 Galaxy Drive Newport Beach, CA File: 8444-10 July 2022 Estimated location of exploratory boring Af Articial ll Qt Terrace deposits Tm Bedrock (Monterey Formation) Contact between geologic units EXPLANATION Af Tm Tm QtQt Qt PL ELEVATION, feetN48°W B B’ 70 100 40 ELEVATION, feet70 100 130 130 40 1010 IDEALIZED PROFILE CL Galaxy Drive HA-6 (projected 10’ NW) TD 5’ HA-4 (projected 9’ SE) TD 8’ HA-2 (projected 5’ SE) TD 12’ HA-3 (proj. 9’ NW) TD 12.5’ ?? ?? ? Anchor PL Existing structure Notes: 1.All elevations estimated; figure is idealized. 2.Actual profiles may vary; based on topographic and geologic interpretation. 2.5:1 line -20-20 0 30 feet Approximate deadman, inferred from construction photos Oblique (apparent) bedding is shown True dip is north (out of page) Limits of proposed new structure 2.1062.106120150084000WW 1000.00 lbs/ft2 1000.00 lbs/ft22.1062.106120150084000Min FSMethod Name2.106Bishop simplified2.099GLE / Morgenstern‐PriceRuHuHu TypeWater SurfacePhi (deg)Cohesion (psf)Strength TypeUnit Weight (lbs/ft3)ColorMaterial Name0None33200Mohr‐Coulomb120Terrace Deposits1CustomWater Surface301400Mohr‐Coulomb100Bedrock0None33275Mohr‐Coulomb120Fill1CustomWater Surface26150Mohr‐Coulomb120QalPressureSafety Factor0.0000.2500.5000.7501.0001.2501.5001.7502.0002.2502.5002.7503.0003.2503.5003.7504.0004.2504.5004.7505.0005.2505.5005.7506.000+3002001000-200-1000100200300400ScenarioExisting Slope - w/ Caisson Support SystemDescriptionCross Section C-C'AnalysisStatic - Global StabilityDrawn ByKAD/RJMFile NameSlide1- 8444-10 C3.slmdDate6/23/2022, 12:31:48 AMProjectChen1424 Galaxy DriveSLIDEINTERPRET 9.023FIGURE EC-3CROSS SECTION C-C' 1 0 0 3 0 2 0 1 0 0 30 feet N Figure 4: Bluff Map 1424 Galaxy Drive Newport Beach, CA File: 8444-00 July 2022 1424G a l a x y D r A’ B’ A B C C’ Base map: County of Orange Maps Online Feet Every reasonable effort has been made to assure the accuracy of the data provided, however, The City of Newport Beach and its employees and agents disclaim any and all responsibility from or relating to any results obtained in its use. Disclaimer: 0 833417 SITE:1424 Galaxy Drive FILE NO: 8444-10 JULY 2022 FIGURE 5 - LOCATION MAP Feet Every reasonable effort has been made to assure the accuracy of the data provided, however, The City of Newport Beach and its employees and agents disclaim any and all responsibility from or relating to any results obtained in its use. Disclaimer: 6/5/2022 0 200100 FILE NO: 8444-10 JULY 2022 FIGURE 6 - AERIAL PHOTO MAP 6/5/22, 10:04 AM Google Maps https://www.google.com/maps/@33.6286905,-117.8893658,126a,35y,270h,39.52t/data=!3m1!1e3?hl=en&authuser=0 1/1 Imagery ©2022 Google, Imagery ©2022 Maxar Technologies, U.S. Geological Survey, Map data ©2022 50 ft FILE NO: 8444-10 JULY 2022 FIGURE 7 - AERIAL IMAGE IN NORTHWEST DIRECTION 1424 6/5/22, 10:00 AM Google Maps https://www.google.com/maps/@33.6287342,-117.8927022,256a,35y,90h,39.45t/data=!3m1!1e3?hl=en&authuser=0 1/1 Imagery ©2022 Google, Imagery ©2022 Maxar Technologies, U.S. Geological Survey, USDA/FPAC/GEO, Map data ©2022 100 ft FILE NO: 8444-10 JULY 2022 FIGURE 8 -AERIAL IMAGE IN SOUTHEAST DIRECTION 1424 6/5/22, 9:59 AM Google Maps https://www.google.com/maps/@33.6295094,-117.8905706,101a,35y,180h,39.53t/data=!3m1!1e3?hl=en&authuser=0 1/1 Imagery ©2022 Google, Imagery ©2022 Maxar Technologies, U.S. Geological Survey, Map data ©2022 20 ft FILE NO: 8444-10 JULY 2022 FIGURE 9 - AERIAL IMAGE IN SOUTHWEST DIRECTION 1424 APPENDIX A REFERENCES APPENDIX A REFERENCES (1424 Galaxy Drive) R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 1. Apex Surveying Inc., Topographic Map, 1424 Galaxy Drive, Newport Beach, CA 92660 APN:117- 671-14, Scale: 1” = 8’, Job No. 20057, June 25, 2020, Sheet 1 of 1. 2. American Society of Civil Engineers (ASCE), 2019, ASCE 7 Hazard Tool, https://asce7hazardtool.online/ 3. Boyle Engineering, 1962, “Construction Specifications for Sheet Pile Bulkhead for Tract No. 4224, Macco Corporation and Harbor Investment Co., Orange County, California,” May. 4. California Building Code, 2019 Edition. 5. California Division of Mines and Geology, 1998, “Seismic Hazards Zones Map, Newport Beach Quadrangle.” 6. California Divisions of Mines and Geology, 2008, “Guidelines for Evaluating and Mitigating Seismic Hazards in California,” Special Publication 117A. 7. City of Newport Beach, Building Department, 1970, “Soil Conditions in Tract 4224 (Dover Shores),” May 22. 8. City of Newport Beach, Department of Community Development, 1978, “Landslide at 1424 Galaxy Drive,” March 16. 9. City of Newport Beach, Building Department, 1978, “Application for Grading Permit,” Nov 22. 10. City of Newport Beach, Department of Community Development, 1979, “Listing of Bluff Failures- Dover Shores,” January 25. 11. Converse Consultants, 1998, “Report of Landslide Investigation, Rear Yard and Natural Bluff Below Lot 72 and 73, 1454 Galaxy Drive, Upper Back Bay Area, Newport Beach, California,” Converse Project No. 97-32619-01, May 14. 12. Converse, Davis Dixon Associates, 1976, “Soil and Geologic Investigation, 1454 Galaxy Drive, Newport Beach, California,” Project No A-75-659-EH, January 9. 13. Department of the Navy, 1982, NAVFAC DM-7.1, Soil Mechanics, Design Manual 7.1, Naval Facilities Engineering Command. 14. Douglas E. Moran, Inc., 1978, “…Stability Calculation,” associated with Landslide Damage, Lots 77, 78 and 79 of Tract 4220, 1430, 1424 and 1418 Galaxy Drive, Newport Beach, California, Calc Sheets 1-3/3 and Direct Shear Test Results, 1 page, Job No.: 78-10, October 25. 15. Douglas E. Moran, Inc., 1978, “Landslide Damage, Lots 77, 78 and 79 of Tract 4220, 1430, 1424 and 1418 Galaxy Drive, Newport Beach, California,” Job No.: 78-10, June 23. 16. Douglas E. Moran/Brittain Poteet, Undated, Excerpted Construction Plan to Stabilize 1424 and 1430 Galaxy Drive After Landsliding in the 1977-78 Rain Season, Newport Beach, California. 17. Evans, Goffman & McCormick, 1973, “Inspection of Landslide at Rear of 1958 Galaxy Drive, Newport Beach, California,” 73-162, January 3. 18. G. A. Nicholl and Associates, Inc., 1974, Specification and Plans, Lot 16, Tract 4224, Dover Shores, Newport Beach, California,” Project 1143-1, May 31. 19. G. A. Nicholl and Associates, Inc., 1974, “Supplemental Slope Stability Calculations, Lot 16, Tract 4224, Dover Shores, Newport Beach, California,” Project 1272, October 1. 20. G. A. Nicholl and Associates, Inc., 1974, “Response to Engineering and Geologic Review Sheet Rear of Lot 16, Tract 4224, Newport Beach, California,” Project 1272, October 15. 21. G. A. Nicholl and Associates, Inc., 1975, Specifications, Plans and Slope Stability Investigation, Lots 11 through 15, Tract 4224, Dover Shores, Newport Beach, California,” Project 1359, July 31. 22. Galaxy Portfolio, 1978-1983, Site Photos. 23. GMU Geotechnical, Inc., 2018, “Geotechnical Investigation, Proposed Single Family Residence, 1392 Galaxy Drive, Lot 80, Tract 4224, Newport Beach, California,” GMU Project No. 18-023-00, March 23. 24. Group Delta Consultants, 1998, “Geotechnical Report, Restoration and Slope Repair, 1454 Galaxy Drive, Newport Beach, California,” Project No 1862-EC01, November 2. APPENDIX A REFERENCES (1424 Galaxy Drive) R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 25. Hart, E. W., and Bryant, W. A., 1997, “Fault-Rupture Hazard Zones in California, Alquist-Priolo Earthquake Fault Zoning Act: California Division of Mines and Geology”, Special Publication 42 (Interim Supplements and Revisions 1999, 2003, and 2007). 26. Jennings, Charles W., et al., 1994, “Fault Activity Map of California and Adjacent Areas,” California Division of Mines and Geology, Geologic Data Map No. 6. 27. Kenneth G. Osborne & Associates, 1975, “Engineering Evaluation for Stabilization and Repair of Residences on Lots 96-100, Tract 4224, Newport Beach, California,” Job No. 74-1208-6, March 6. 28. Leroy Crandell & Associates, 1961, Log of Boring 5 (12/1/1961), Log of Boring 7 (12/17/1961), Log of Boring 29 (1/24/1962). 29. Martin, G. R. and Lew, M., 1999, “Recommended Procedures for Implementation of DMG Special Publication 117, Guidelines for Analyzing and Mitigating Liquefaction Hazards in California,” SCEC, March. 30. Morton and Miller, 1981, Geologic Map of Orange County, CDMG Bulletin 204. 31. Morton, P. K., Miller, R. V., and Evans, J. R., 1976, “Environmental Geology of Orange County, California, California Division of Mines and Geology,” Open File Report 79-8 LA. 32. Morton, Douglas M., and Miller, Fred K., Compilers, 2006, “Geologic Map of the San Bernardino and Santa Ana 30’ X 60’ Quadrangles, California,” U. S. Geological Survey Open File Report 2006- 1217. 33. Petersen, M. D., Bryant, W. A., Cramer, C. H., Cao, T., Reichle, M. S., Frankel, A. D., Lienkaemper, J. J., McCrory, P. A., and Schwartz, D. P., 1996, “Probabilistic Seismic Hazard Assessment for the State of California,” Department of Conservation, Division of Mines and Geology, DMG Open-File Report 96-08, USGS Open File Report 96-706. 34. Philip J. Nielsen Design & Drafting, 2020, “A Remodel and Addition for: Eddie Chen, 1424 Galaxy Drive, Newport Beach, California 92660, Sheet A-3, July 9. 35. PMA Consulting, Inc., 2022 “Retaining Wall Conditions Report, Eddie Chen; Applicant, 1424 Galaxy Drive, City of Newport Beach, County of Orange,” PMA Job #47122, May 17. 36. R McCarthy Consulting, Inc., 2021, “Supplemental Geotechnical Report, Proposed New Custom Home, Tract 4424, Lot 78, 1424 Galaxy Drive, Newport Beach, California, APN: 117-671-14,” File No. 8444-10, Report No. R4-8444, dated July 9. 37. R McCarthy Consulting, Inc., 2021, “Response to City Review, Geotechnical Report Review Checklist, 2nd Review (4/29/21), Tract 4224, Lot 78, 1424 Galaxy Drive, Newport Beach, California,” Plan Check No: 0411-2021, File No. 8444-00, Report No. R3-8444, dated May 24. 38. R McCarthy Consulting, Inc., 2021, “Response to City Review, Geotechnical Report Review Checklist, 1st Review (2/27/21), Tract 4224, Lot 78, 1424 Galaxy Drive, Newport Beach, California,” Plan Check No: 0411-2021,” File No. 8444-00, Report No. R2-8444, dated April 5. 39. R McCarthy Consulting, Inc., 2020, “Geotechnical Investigation, Proposed Residential Construction for Remodel, Tract 4424, Lot 78, 1424 Galaxy Drive, Newport Beach, California, APN: 117-671-14,” File No. 8444-00, Report No. R1-8444, dated November 4. 40. Strata-Tech, Inc., 2009, “Limited Geotechnical Investigation, Distressed Rear Yard Planter Boxes, 1401 Dolphin Terrace, Corona Del Mar, California,” W.O. 260809, December 9. 41. Structural Engineers Association of California (SEAOC), 2019, OSHPD Seismic Design Maps, https://seismicmaps.org/ 42. Tan, Siang, S., and Edgington, William J., 1976, "Geology and Engineering Geology of the Laguna Beach Quadrangle, Orange County, California," California Division of Mines and Geology, Special Report 127. 43. Vedder, J. G., Yerkes, R. F., and Schoellhamer, J. E., 1957, Geologic Map of the San Joaquin Hills-San Juan Capistrano Area, Orange County, California, U. S. Geological Survey, Oil and Gas Investigations Map OM-193. 44. Zeiser Kling Consultants, Inc., 1998, “Geotechnical Report of Bluff Slope Failure Investigation, 1448 Galaxy, Newport Beach, California.,” PN 98038-01, November 2. APPENDIX A REFERENCES (1424 Galaxy Drive) R McCarthy Consulting, Inc. 23 Corporate Plaza, Suite 150, Newport Beach, CA 92660 AERIAL PHOTO REFERENCES FOR FLIGHTS REVIEWED IN THIS ANALYSIS 1. County of Orange, 1970, Aerial Photograph, Flight AMI-OC-70, Frame Count: 132, Acquired from: Landiscor Aerial, Scale: 1:36,000, Dated: October 28. 2. County of Orange, 1971, Aerial Photograph, Flight AMI-OC-71, Acquired from: Landiscor Aerial, Scale: 1:36,000, Dated: April 5. 3. County of Orange, 1972, Aerial Photograph, Flight AMI-OC-72A, Frame Count: 118, Acquired from: Landiscor Aerial, Scale: 1:36,000, Dated: December 5. 4. County of Orange, 1974, Aerial Photograph, Flight AMI-OC-74, Frame Count: 37, Acquired from: Landiscor Aerial, Scale: 1:36,000, Altitude 18,000, dated January 25. 5. County of Orange, 1938, Aerial Photograph, Flight AXK-1938, Frame Count: 780, Directional Orientation: North-South, Flown by: Laval Company, Inc, Scale: 1:20,000, Altitude: 13,750, Dated July 15. 6. County of Orange, 1953, Aerial Photograph, Flight AXK-1953, Frame Count: 626, Directional Orientation: North-South, Flown by: Pacific Air Industries, Scale:1:20,000, Dated: June 30. 7. County of Los Angeles and Orange, 1927, Aerial Photograph, Flight C-135, Frame Count: 51, Directional Orientation: Northeast-Southwest, Flown by: Fairchild Aerial Surveys, Scale: 1:18,000, Dated: November 3. 8. County of Los Angeles, Orange, and San Bernardino, 1938, Aerial Photograph, Flight C-5029, Frame Count: 159, Directional Orientation: North-South, Altitude: 15,840, Flown by: Fairchild Aerial Surveys, Scale: 1:30,000, Dated: March 4. 9. California: Del Norte, Humboldt, Los Angeles, Marin, Mendocino, Monterey, Orange, San Diego, San Francisco, San Luis Obispo, San Mateo, Santa Barbara, Santa Cruz, Sonoma, Ventura, 2001- 2002, Aerial Photograph, Flight CCC-BQK-C, Frame Count: 2910, Altitude: 6,000, Flown by: I.K. Curtis Services, Inc. and American Aerial Surveys, Inc., Scale: 1:12,000, Dated: January 23. 10. County of Orange, 1998, Aerial Photograph, Flight EAG-OC-98, Frame Count: 50, Acquired from: Eagle Aerial Imaging, Scale: 1:42,000, Dated: March 10. 11. County of Orange, 1960, Aerial Photograph, Flight PAI-OC-60, Frame Count: 279, Flown by: Pacific Air Industries, Altitude: 12,000, Scale: 1:24,000, Directional Orientation: Various, Dated: December 13. 12. County of Orange, Los Angeles, Riverside, San Bernardino, San Diego, and Ventura, 1977, Aerial Photograph, Flight TG-7700, Frame Count: 766, Flown by: Teledyne Geotronics, Altitude: 12,000, Scale: 1:24,000, Directional Orientation: East-West, Dated: July 31. APPENDIX B BORING LOGS IN SUPPORT OF SLOPE STABILITY ANALYSIS Zeiser Kling Consultants, Inc. (1998) 1448 Galaxy Drive Converse Consultants (1998) 1454 Galaxy Drive GMU Geotechnical, Inc. (2018) 1392 Galaxy Drive R McCarthy Consulting, Inc (2020) 1424 Galaxy Drive DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 107' BORING NO: HA-1 FILE NO: 8444-00 FIGURE B-2 BY: SPC ARTIFICIAL FILL (Af): Dark brown silty CLAY, moist, soft, mottled Total Depth: 4.3 feet (Refusal on obstruction - rock or concrete)No groundwater SITE LOCATION: 1424 Galaxy DriveBackyard planter Gray brown clayey SILT, very moist, firm/compacted, diatomaceous Red brown clayey SAND, moist, medium dense/compacted Gray-brn silty CLAY, moist, firm/compacted, obstruction at 4.3' DATE: 8/20/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other 14___6” CH ML SC CH 65.0 56 Max Dry Density (97 pcf, 20.0%) Expansion Index (EI = 79) Atterberg Limits (LL = 55, PI = 26) Grain Size (28.0% passing #200) Chemical Tests DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 103' BORING NO: HA-2 FILE NO: 8444-00 FIGURE B-3 BY: GM ARTIFICIAL FILL (Af): Medium brown sandy SILT, moist, sloft to firm, planter soil, roots upper 6" D1 at 3’: Medium brown sandy SILT, moist, firm/compacted, mottled with gray brown silt, abundant root fragments D2 at 7’: Red brown sandy SILT, moist, firm/compacted, mottled, diatomaceous, mixed root fragments TERRACE DEPOSITS (Qt): At 9’: Tan brown silty SAND, moist, medium dense, abundant shell fragments, medium to coarse grained, uniform material D3 at 11’: White-gray SILT, moist, dense, layered, diatomaceous, possible siltstone bedrock contact Total Depth: 12 feet (refusal in dense silt) No groundwater SITE LOCATION: 1424 Galaxy DriveRear lawn NWCDATE: 8/25/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other 30___6” ML 20___6”ML 50___6” 18.2 103 16.5 104 52.9 80 SM ML DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 107' BORING NO: HA-3 FILE NO: 8444-00 FIGURE B-4 BY: GM ARTIFICIAL FILL (Af): Medium brown sandy SILT, planter soil, soft to firm, moist, roots to 6" @ 6" Red brown silty SAND, moist, compacted D1 at 4’: Red brown silty SAND, moist, medium dense/compacted, mottled with gray silt, abundant carbonate deposits D2 at 8’: Yellow brown SAND, moist, medium dense, fine grained, abundant mica, uniform TERRACE DEPOSITS (Qt): Red brown silty SAND, moist, medium dense, uniform White-gray SILT, moist, medium dense to dense, layered (attempted to sample, sampler unable to penetrate rock), possible siltstone contact Total Depth: 12.5 feet (refusal) No groundwater SITE LOCATION: 1424 Galaxy DriveRear yard - middleDATE: 8/25/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other 25___6” SM 20___6”SM 11.8 103 7.1 98 ML ML DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 107' BORING NO: HA-4 FILE NO: 8444-00 FIGURE B-5 BY: GM ARTIFICIAL FILL (Af): Medium brown SILT, moist, soft to firm, roots @6" Medium brown silty SAND, moist, compacted D1 at 2’: Medium brown silty SAND, moist, medium dense, mottled with gray silt, shell fragments D2 at 7’: Tan brown silty SAND, moist, medium dense, fine grained, lots of binder TERRACE DEPOSITS (Qt): Total Depth: 8 feet (refusal on dense terrace deposits) No groundwater SITE LOCATION: 1424 Galaxy DriveRear yard near north corner of houseDATE: 8/26/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other 18___6”SM 50___4” SM 14.7 104 9.5 83 ML Tan-brown silty SAND, moist DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 107' BORING NO: HA-5 FILE NO: 8444-00 FIGURE B-6 BY: GM ARTIFICIAL FILL (Af): Pale gray sandy SILT, moist, firm Pale gray sandy SILT, moist, medium dense/compacted, mottled with red brown silty SAND Red brown silty SAND, moist, medium dense/compacted, scattered rock fragments, mottled gray silt D2 at 10’: Yellow brown SAND, moist, medium dense, fine grained, less binder TERRACE DEPOSITS (Qt): D1 at 6’: Red brown silty SAND, moist, medium dense, fine to medium grained, strong binder in sections D3 at 14’: Gray-white SILT, moist, medium dense, layered Total Depth: 15 feet (refusal) No groundwater SITE LOCATION: 1424 Galaxy DriveRear yard near east corner of houseDATE: 8/26/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other 50___4”SM 36___6”SM 40___4” 12.7 87 6.9 105 37.9 75 ML SM ML DEPTHUSCSBLOW COUNTIN-PLACE SAMPLEBAG SAMPLEMOISTURE (%)DRY DENSITY (PCF)MATERIAL DESCRIPTION NOTES DEPTHLOG OF BORING R MCCARTHY CONSULTING, INC. 5 10 15 20 25 5 10 15 20 25 EQUIPMENT: Hand auger SURFACE ELEVATION: +/- 106' BORING NO: HA-6 FILE NO: 8444-00 FIGURE B-7 BY: GM ARTIFICIAL FILL (Af): Medium brown SILT, planter soil, moist, firm, roots to 6" D1 at 2’: Pale gray SILT, moist, firm to stiff/compacted, mottled with silty sand, diatoms TERRACE DEPOSITS (Qt): D2 at 4’: Medium brown silty SAND, moist/wet, medium dense, fine to medium grained Total Depth: 5 feet No groundwater SITE LOCATION: 1424 Galaxy DriveFront entrance DATE: 8/26/20 “At x’:” always at front. Only cap first letter of sentence. Color, fineness SOIL TYPE, material classification, moisture, density, other ML 25___6” 25___6”SM 42.1 76 11.4 109 APPENDIX C LABORATORY TEST RESULTS - DIRECT SHEAR TESTING IN SUPPORT OF SLOPE STABILITY ANALYSES Rate of Shear 0.005 in/min Sample Type Undisturbed Date:8444-00 DIRECT SHEAR TEST File No.:C-6Figure No.:October - 2020 Sample Identification Shear Strength Angle of Friction - degrees (Peak) Cohesion - psf (Ultimate)125 29.0 Angle of Friction - degrees (Ultimate) 28.0113.1 Moisture Content (%) 20.0 HA-3 @ 8' Characteristics Cohesion - psf (Peak)150 Dry Density (pcf) 0 1000 2000 3000 4000 5000 6000 0 1000 2000 3000 4000 5000 6000Shearing Stress (psf)Normal Stress (psf) Moran (1978) 1424 Galaxy Drive Zeiser Kling Consultants, Inc. (1998) 1448 Galaxy Drive Converse Consultants (1998) 1454 Galaxy Drive GMU Geotechnical, Inc. (2018) 1392 Galaxy Drive